URLhaus: 176-65-139-239 Malicious URLs

Hunt Hypothesis

This hunt detects adversary activity involving the consumption of specific malicious URLs identified by URLhaus at IP address 176.65.139.239, which often indicate early-stage phishing or command-and-control communications. A SOC team should proactively search for these indicators in Azure Sentinel to rapidly identify potential lateral movement or data exfiltration attempts before they escalate into broader incidents.

IOC Summary

Threat: 176-65-139-239 Total URLs: 2 Active URLs: 0

KQL: Url Dns Hunt

// Hunt for DNS resolution of URLhaus malicious domains
// Threat: 176-65-139-239
let malicious_domains = dynamic(["176.65.139.239"]);
DnsEvents
| where Name has_any (malicious_domains)
| project TimeGenerated, Computer, Name, IPAddresses
| order by TimeGenerated desc

KQL: Url Proxy Hunt

// Hunt for web traffic to URLhaus malicious domains
let malicious_domains = dynamic(["176.65.139.239"]);
CommonSecurityLog
| where RequestURL has_any (malicious_domains) or DestinationHostName has_any (malicious_domains)
| project TimeGenerated, SourceIP, RequestURL, DestinationHostName, DeviceAction
| order by TimeGenerated desc

Required Data Sources

References

• URLhaus

False Positive Guidance

Here are 4 specific false positive scenarios for the URLhaus: 176-65-139-239 Malicious URLs detection rule, including suggested filters and exclusions tailored for a legitimate enterprise environment:

• Scenario: Automated Security Scanner Probing

  • Context: Internal vulnerability management tools (e.g., Tenable Nessus, Qualys, or Rapid7 InsightVM) periodically probe external URLs to verify reachability or scan for known threats. These scanners often generate HTTP requests to the IP 176.65.139.239 as part of a scheduled discovery job, triggering the rule even though no human user is interacting with the URL.
  • Suggested Filter/Exclusion: Create an exclusion based on the source host identity. Exclude alerts where the source hostname or device_type matches known scanner assets (e.g., *scanner-01, *qualys-agent) OR exclude traffic originating from specific management VLANs (e.g., Source_IP in 10.20.50.0/24).

• Scenario: Cloud Backup and Synchronization Traffic

  • Context: Enterprise backup solutions like Veeam, Rubrik, or Microsoft OneDrive for Business utilize cloud endpoints for metadata synchronization and policy updates. The IP 176.65.139.239 may be a legitimate CDN node or API endpoint used by these services to fetch configuration manifests, which the rule incorrectly flags as malicious due to URL pattern matching.
  • Suggested Filter/Exclusion: Implement a process-based exclusion. If the initiating process name matches known backup agents (e.g., VeeamAgent.exe, OneDrive.exe, RubrikService), suppress the alert. Alternatively, exclude traffic